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<h1>ExtendedItem</h1>
<p>Represents an extended item, provide BIRT extenion capability.</p>

<h3>Description</h3>
Represents an extended item element. The extended report item
allows third-party developers to create report items that work within BIRT
virtually identically to BIRT-defined items. 

<p>Extended items can use the user-properties discussed above to define properties.
Extended items are defined in a Java plug-in that contributes behavior to the Eclipse 
Report Developer, to the Factory and to the Presentation Engine. 

<p>The extended item can fully participate with the other BIRT extension facilities, 
meaning that report developers can add properties and scripts to an extended item,
providing a very powerful way to create application-specific functionality.
An extended item is defined by a plug-in. The plug-in is specific to BIRT,
and is different from an Eclipse plug-in. Each item plug-in has four parts:
<ul>
<li>Design: handles the model that describes the report item.
<li>User Interface: the UI displayed for the item. This is in the form of an
Eclipse plug-in.
<li>Factory: how to gather the data for the extended item, and compute its
default size in the Factory.
<li>Presentation: how to render the extended item when rendering the report
to HTML, PDF or other formats.
</ul>

<h3>See Also</h3>

<h2 class="method">onCreate</h2>
<p>Script executed when the element is created in the Factory.</p>

<h3>Description</h3>
<p>Executed when the element is created in the Factory. Called after the item is created, but before 
the item is saved to the report document file. See the scripting spec for additional information 
about this script. Applications should perform visual customization in the on-render script instead.</p>

<h2 class="method">onPrepare</h2>
<p>It is for a script startup phase. No data binding yet. The design of an element can be changed here.</p>

<h3>Description</h3>
<p>It is for a script startup phase. No data binding yet. The design of an element can be changed here.</p>

<h2 class="method">onRender</h2>
<p>Script executed when the element is prepared for rendering in the Presentation engine.</p>

<h3>Description</h3>
<p>Executed when the element is prepared for rendering in the Presentation engine. Changes made to the 
element are written to the target output format, but not saved to the report document file. This is the
preferred place for visual customizations.</p>

<h2 class="property">extensionName</h2>
<p>A unique extension name to identify the extension</p>

<h3>Description</h3> 

<p>Indicates which extension this extended item is extended from. 

<p>Using this name, BIRT can get the 
extension definition. The name is an internal name for an implementation of extension.</p>

<h2 class="property">filter</h2>
<p>A list of filter conditions that can be applied to the extended item</p>

<h3>Description</h3>
<p>A list of filter conditions that can be applied to the extended item</p>

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